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101.
By applying a microwave magnetic field parallel to an external magnetic field, ESR of naphthalene, quinoxaline, quinoline and isoquinoline in their phosphorescent triplet states has been studied at 77 K. The proton hyperfine structures in the Δm = ± 2 transitions were distinctly resolved, especially when the stretched film was used as a host, compared with observations in ethanol glasses. The assignment of these ESR signals was carried out with the aid of the stretched-film method. 相似文献
102.
2-Aminomethylpyridine readily reacted with Co(II) ion to give a chelate complex which reacted with oxygen to form, presumably, a μ-peroxodicobalt(III) complex or a Co(III)- complex, and finally it was transformed to 2,3,5,6-tetra(2-pyridyl) pyrazine. 相似文献
103.
Kazuo Soga Iwakazu Hattori Jiro Kinoshita Sakuji Ikeda 《Journal of polymer science. Part A, Polymer chemistry》1977,15(3):745-753
Copolymerization of ethylene oxide (EO) and sulfur dioxide (SO2) was conducted by using a variety of amines as catalyst. Aromatic tertiary amines such as quinoline and pyridine were found to show the best catalytic property of the various amines, and copolymerization was carried out in the temperature range between 0 and 80°C with the use of quinoline. The copolymerization rate was approximately first-order in quinoline, EO, and also SO2. The copolymer, was always composed of the two monomers: 1:1 ratio, independent of the initial concentration of the monomers. The copolymer obtained was a transparent viscous material which decomposed at 218°C to afford a considerable amount of ethylene sulfite. Spectroscopic analysis of the copolymer combined with the results of elemental analysis indicates the copolymer to have the structure The polymerizability of ethylene sulfite, which might be considered an intermediate compound in the copolymerization, was also examined at 60°C for 4 hr in the presence of quinoline, and it was found that ethylene sulfite could not be polymerized under these conditions. 相似文献
104.
105.
106.
Takahashi T Kuroiwa S Ogura T Yoshikawa S 《Journal of the American Chemical Society》2005,127(28):9970-9971
The process of dioxygen reduction catalyzed by cytochrome c oxidase was investigated by examining intact porcine mitochondrial preparations using a novel time-resolved resonance Raman measurement system at experimental accuracy levels equivalent to those of the reaction system of the solubilized and purified enzyme. The resonance Raman bands assignable to the initial three intermediates were detected at frequencies identical to those observed with purified enzyme preparations. However, the lifetime of the initial intermediate (the oxygenated species) in the mitochondrial preparation was found to be significantly longer than that observed in purified preparations, suggesting that control of the stability of the oxygenated species is imposed by the mitochondrial membrane system. 相似文献
107.
108.
Mikio Hori Tadashi Kataoka Hiroshi Shimizu Sachio Ohno Kenichi Narita Hiroaki Takayanagi Haruo Ogura Yoichi Iitaka 《Tetrahedron letters》1979,20(44):4315-4318
The first success of an X-ray analysis of a thiabenzene derivative, 1-benzoyl-2-methyl-2-thianaphthalene is described. 相似文献
109.
H. Ogura 《Chemistry of Heterocyclic Compounds》1981,17(7):633-641
Primarily the studies of the author dealing with the synthesis of analogs of nucleosides by cyclization of derivatives of monosaccharides, viz., Schiff bases, hydrazones, thioureas, thiocarbamates, thiosemicarbazones, thiobiurets, and keto isothiocyanates, are correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 867–877, July, 1981. 相似文献
110.
We examined whether a protein could catalyze two-phase oxidation of formaldehyde dithioacetals with aqueous sodium metaperiodate and bovine serum albumin was found to be effective and give the corresponding S-oxides in optically active forms. 相似文献